The number of travellers passing through Dubai International airport dipped last year for the first time in 20 years but the airport remained the world's busiest for international passengers, authorities said on Wednesday.

Dubai Airport, one of the world's biggest aviation hubs, said Thursday it would carry out thermal screening of all passengers arriving from China amid an outbreak of a deadly virus.

It rises out of what were once rolling sand dunes stretching toward the horizon, a feverish construction site by tempo and temperature that has tens of thousands of workers building what looks like a new city in the desert of Dubai.

This is the site of Expo 2020, a world's fair that will be hosted by a city-state that is already home to the world's tallest building, the busiest airport for international travel, an indoor ski slope and other modern marvels.

With the highest tower in the world, grand commercial centres and artificial islands, Dubai projects an image of prosperity, even as the city-state races to court investors to bolster a flagging economy.

The British-flagged oil tanker Stena Impero headed into port in Dubai on Saturday after being held off the Iranian port of Bandar Abbas for more than two months, according to authorities and a tracking website.

Dubai International Airport, the world's busiest airport for international travel, has briefly halted flights over an alleged drone sighting.

The airport says it halted flights from 10:13 a.m. to 10:45 a.m. on Friday over "suspected drone activity." It says flights were later resumed.

A princess who tried to flee the United Arab Emirates months ago is "a troubled young woman", a former UN human rights chief said on Thursday after meeting her this month.

Delays and flight cancellations persisted Thursday at Dubai International Airport, a day after an Emirates airliner suffered a crash-landing that saw all 300 people onboard survive while a firefighter was killed.

The cause of the crash-landing of Flight No. EK521, a Boeing 777-300 coming from the southern Indian city of Thiruvananthapuram, also remained unclear.

Hundreds of passengers fled an Emirates airliner that crash-landed and caught fire in Dubai Wednesday, resulting in the death of a firefighter and a four-hour shutdown of the busy airport but no other fatalities.

Two Turkish generals serving in Afghanistan have been detained in Dubai on suspicion of links to the July 15 failed coup against President Recep Tayyip Erdogan, a Turkish official said Tuesday.